You may have heard of Gregor Johann Mendel. He was the monk whose research on peas led to the understanding of how organisms inherit traits from their parents. Mendel studied how certain physical traits were passed from one generation of peas to the next. This research lead to the modern scientific field of genetics.
Since his pioneering research, scientists have discovered how DNA, the genetic code that tells an organism how to work and grow, is copied from one generation and then rewritten and recombined for the next generation. If you major in genetics, you’ll look at inheritance (including hereditary diseases) and the genetic path of evolution.